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<a href="default__init__allocator_8hpp.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a id="l00001" name="l00001"></a><span class="lineno">    1</span><span class="comment">/* Flow-IPC: Core</span></div>
<div class="line"><a id="l00002" name="l00002"></a><span class="lineno">    2</span><span class="comment"> * Copyright 2023 Akamai Technologies, Inc.</span></div>
<div class="line"><a id="l00003" name="l00003"></a><span class="lineno">    3</span><span class="comment"> *</span></div>
<div class="line"><a id="l00004" name="l00004"></a><span class="lineno">    4</span><span class="comment"> * Licensed under the Apache License, Version 2.0 (the</span></div>
<div class="line"><a id="l00005" name="l00005"></a><span class="lineno">    5</span><span class="comment"> * &quot;License&quot;); you may not use this file except in</span></div>
<div class="line"><a id="l00006" name="l00006"></a><span class="lineno">    6</span><span class="comment"> * compliance with the License.  You may obtain a copy</span></div>
<div class="line"><a id="l00007" name="l00007"></a><span class="lineno">    7</span><span class="comment"> * of the License at</span></div>
<div class="line"><a id="l00008" name="l00008"></a><span class="lineno">    8</span><span class="comment"> *</span></div>
<div class="line"><a id="l00009" name="l00009"></a><span class="lineno">    9</span><span class="comment"> *   https://www.apache.org/licenses/LICENSE-2.0</span></div>
<div class="line"><a id="l00010" name="l00010"></a><span class="lineno">   10</span><span class="comment"> *</span></div>
<div class="line"><a id="l00011" name="l00011"></a><span class="lineno">   11</span><span class="comment"> * Unless required by applicable law or agreed to in</span></div>
<div class="line"><a id="l00012" name="l00012"></a><span class="lineno">   12</span><span class="comment"> * writing, software distributed under the License is</span></div>
<div class="line"><a id="l00013" name="l00013"></a><span class="lineno">   13</span><span class="comment"> * distributed on an &quot;AS IS&quot; BASIS, WITHOUT WARRANTIES OR</span></div>
<div class="line"><a id="l00014" name="l00014"></a><span class="lineno">   14</span><span class="comment"> * CONDITIONS OF ANY KIND, either express or implied.</span></div>
<div class="line"><a id="l00015" name="l00015"></a><span class="lineno">   15</span><span class="comment"> * See the License for the specific language governing</span></div>
<div class="line"><a id="l00016" name="l00016"></a><span class="lineno">   16</span><span class="comment"> * permissions and limitations under the License. */</span></div>
<div class="line"><a id="l00017" name="l00017"></a><span class="lineno">   17</span><span class="comment"></span> </div>
<div class="line"><a id="l00018" name="l00018"></a><span class="lineno">   18</span><span class="comment">/// @file</span></div>
<div class="line"><a id="l00019" name="l00019"></a><span class="lineno">   19</span><span class="comment"></span><span class="preprocessor">#pragma once</span></div>
<div class="line"><a id="l00020" name="l00020"></a><span class="lineno">   20</span> </div>
<div class="line"><a id="l00021" name="l00021"></a><span class="lineno">   21</span><span class="preprocessor">#include &lt;memory&gt;</span></div>
<div class="line"><a id="l00022" name="l00022"></a><span class="lineno">   22</span> </div>
<div class="line"><a id="l00023" name="l00023"></a><span class="lineno"><a class="line" href="namespaceipc_1_1util.html">   23</a></span><span class="keyword">namespace </span><a class="code hl_namespace" href="namespaceipc_1_1util.html">ipc::util</a></div>
<div class="line"><a id="l00024" name="l00024"></a><span class="lineno">   24</span>{</div>
<div class="line"><a id="l00025" name="l00025"></a><span class="lineno">   25</span><span class="comment"></span> </div>
<div class="line"><a id="l00026" name="l00026"></a><span class="lineno">   26</span><span class="comment">/**</span></div>
<div class="line"><a id="l00027" name="l00027"></a><span class="lineno">   27</span><span class="comment"> * Allocator adaptor (useful for, e.g., `vector` that skips zero-filling) that turns a value-initialization</span></div>
<div class="line"><a id="l00028" name="l00028"></a><span class="lineno">   28</span><span class="comment"> * `T()` into a default-initialization for those types, namely PoDs, for which default-initialization is a no-op.</span></div>
<div class="line"><a id="l00029" name="l00029"></a><span class="lineno">   29</span><span class="comment"> *</span></div>
<div class="line"><a id="l00030" name="l00030"></a><span class="lineno">   30</span><span class="comment"> * ### Rationale (why) ###</span></div>
<div class="line"><a id="l00031" name="l00031"></a><span class="lineno">   31</span><span class="comment"> * Suppose you have `vector&lt;uint8_t&gt; v(10);`.  This will create a buffer and fill with at least 10 zeroes.</span></div>
<div class="line"><a id="l00032" name="l00032"></a><span class="lineno">   32</span><span class="comment"> * What if you want it *not* do this?  Maybe you don&#39;t want it for performane.</span></div>
<div class="line"><a id="l00033" name="l00033"></a><span class="lineno">   33</span><span class="comment"> * Actually, consider an even sneakier situation that involves correctness, not just perf.  Suppose you</span></div>
<div class="line"><a id="l00034" name="l00034"></a><span class="lineno">   34</span><span class="comment"> * have `vector&lt;uint8_t&gt; v` with `.capacity() == 10` and `.size() == 0`, but you&#39;re letting some 3rd-party code</span></div>
<div class="line"><a id="l00035" name="l00035"></a><span class="lineno">   35</span><span class="comment"> * operate in range `[v.begin(), v.begin() + v.capacity())`, and you&#39;re using `.size()` as a store of the result</span></div>
<div class="line"><a id="l00036" name="l00036"></a><span class="lineno">   36</span><span class="comment"> * the 3rd-party operation.  Say the 3rd party (e.g., a builder library) performs its op (serialization)</span></div>
<div class="line"><a id="l00037" name="l00037"></a><span class="lineno">   37</span><span class="comment"> * and reports that it has used exactly 7 bytes.  Now you call `v.resize(7)`.  The problem: this will fill the first</span></div>
<div class="line"><a id="l00038" name="l00038"></a><span class="lineno">   38</span><span class="comment"> * 7 bytes of the range with zeroes, wiping out the builder&#39;s work.  Of course you could have solved this</span></div>
<div class="line"><a id="l00039" name="l00039"></a><span class="lineno">   39</span><span class="comment"> * by keeping `.capacity() == .size() == 10` at all times and marking down the serialization&#39;s size in a separate</span></div>
<div class="line"><a id="l00040" name="l00040"></a><span class="lineno">   40</span><span class="comment"> * variable.  That&#39;s a bit sad though: you have a perfectly nice potential holder of the size, the `vector` inner</span></div>
<div class="line"><a id="l00041" name="l00041"></a><span class="lineno">   41</span><span class="comment"> * `m_size` (or whatever it is called), but you cannot use it due to the value-initializing behavior of `vector`.</span></div>
<div class="line"><a id="l00042" name="l00042"></a><span class="lineno">   42</span><span class="comment"> *</span></div>
<div class="line"><a id="l00043" name="l00043"></a><span class="lineno">   43</span><span class="comment"> * The link</span></div>
<div class="line"><a id="l00044" name="l00044"></a><span class="lineno">   44</span><span class="comment"> *   https://stackoverflow.com/questions/21028299/is-this-behavior-of-vectorresizesize-type-n-under-c11-and-boost-container/21028912#21028912</span></div>
<div class="line"><a id="l00045" name="l00045"></a><span class="lineno">   45</span><span class="comment"> * contains a nice solution in the form of an allocator adaptor which can be set as the `Allocator` template param</span></div>
<div class="line"><a id="l00046" name="l00046"></a><span class="lineno">   46</span><span class="comment"> * of a `vector` (etc.), adapting the normal allocator used; whether that&#39;s the typical heap-allocating `std::allocator`</span></div>
<div class="line"><a id="l00047" name="l00047"></a><span class="lineno">   47</span><span class="comment"> * or something more exotic (e.g., SHM-allocating ipc::shm::stl::Stateless_allocator).  cppreference.com</span></div>
<div class="line"><a id="l00048" name="l00048"></a><span class="lineno">   48</span><span class="comment"> * `vector::resize()` page even links to that in &quot;Notes&quot; about this problem!</span></div>
<div class="line"><a id="l00049" name="l00049"></a><span class="lineno">   49</span><span class="comment"> *</span></div>
<div class="line"><a id="l00050" name="l00050"></a><span class="lineno">   50</span><span class="comment"> * ### What it does (what/how) ###</span></div>
<div class="line"><a id="l00051" name="l00051"></a><span class="lineno">   51</span><span class="comment"> * The allocator works as follows: Suppose the STL-compliant container, having raw-allocated a buffer `sizeof(T)`</span></div>
<div class="line"><a id="l00052" name="l00052"></a><span class="lineno">   52</span><span class="comment"> * bytes long, at `void* p`, requests to in-place-construct a `T{}` (a/k/a `T()`) at `p`.  That is what, e.g.,</span></div>
<div class="line"><a id="l00053" name="l00053"></a><span class="lineno">   53</span><span class="comment"> * `vector::resize(size_t)` does: it *value-initializes* the `T` at address `p`.  Now there are two possibilities:</span></div>
<div class="line"><a id="l00054" name="l00054"></a><span class="lineno">   54</span><span class="comment"> *   - `T` is a PoD (plain old data-type): value-initialization `T t{};` *does not equal*</span></div>
<div class="line"><a id="l00055" name="l00055"></a><span class="lineno">   55</span><span class="comment"> *     default-initialization `T t;`.  The latter leaves pre-existing (possibly garbage) in `t`.  The former</span></div>
<div class="line"><a id="l00056" name="l00056"></a><span class="lineno">   56</span><span class="comment"> *     does a deterministic initialization; e.g., if `T` is `int` then it zeroes `t`.</span></div>
<div class="line"><a id="l00057" name="l00057"></a><span class="lineno">   57</span><span class="comment"> *   - `T` is not a PoD: value-initialization `T t{}` *does* equal default-initialization `T t`.  They will both</span></div>
<div class="line"><a id="l00058" name="l00058"></a><span class="lineno">   58</span><span class="comment"> *     default-construct `T` via `T::T()`.</span></div>
<div class="line"><a id="l00059" name="l00059"></a><span class="lineno">   59</span><span class="comment"> *</span></div>
<div class="line"><a id="l00060" name="l00060"></a><span class="lineno">   60</span><span class="comment"> * The allocator adaptor changes the *former* bullet point to act like the *latter* bullet point;</span></div>
<div class="line"><a id="l00061" name="l00061"></a><span class="lineno">   61</span><span class="comment"> * while making no changes for non-PoD `T`s.  For PoD `T`s:</span></div>
<div class="line"><a id="l00062" name="l00062"></a><span class="lineno">   62</span><span class="comment"> * The container will ask to do `T t{}` (a/k/a `T t = T()`), but what will happen in reality is `T t;` instead.</span></div>
<div class="line"><a id="l00063" name="l00063"></a><span class="lineno">   63</span><span class="comment"> * Or, in plainer English, it&#39;s gonna make it so that `int`s and `float`s and simple `struct`s and stuff</span></div>
<div class="line"><a id="l00064" name="l00064"></a><span class="lineno">   64</span><span class="comment"> * don&#39;t get auto-zeroed by containers when default-creating them on one&#39;s behalf.</span></div>
<div class="line"><a id="l00065" name="l00065"></a><span class="lineno">   65</span><span class="comment"> *</span></div>
<div class="line"><a id="l00066" name="l00066"></a><span class="lineno">   66</span><span class="comment"> * ### What about `flow::util::Blob`? ###</span></div>
<div class="line"><a id="l00067" name="l00067"></a><span class="lineno">   67</span><span class="comment"> * `Blob`, as of this writing, specifically exists -- among a few other reasons -- to avoid the default-zeroing</span></div>
<div class="line"><a id="l00068" name="l00068"></a><span class="lineno">   68</span><span class="comment"> * that a `vector&lt;uint8_t&gt;` would do.  So why this Default_init_allocator then?  Indeed!  You should use `Blob`</span></div>
<div class="line"><a id="l00069" name="l00069"></a><span class="lineno">   69</span><span class="comment"> * instead of `vector&lt;uint8_t&gt;`; you&#39;ll get quite a few goodies as a result.  The problem: `Blob` always</span></div>
<div class="line"><a id="l00070" name="l00070"></a><span class="lineno">   70</span><span class="comment"> * heap-allocates.  Update: But, happily, now `flow::util::Basic_blob&lt;Allocator&gt;` exists (and `Blob` is</span></div>
<div class="line"><a id="l00071" name="l00071"></a><span class="lineno">   71</span><span class="comment"> * a heap-allocating case of it) and plays well with SHM-allocating allocators.  Therefore Default_init_allocator</span></div>
<div class="line"><a id="l00072" name="l00072"></a><span class="lineno">   72</span><span class="comment"> * is less useful.</span></div>
<div class="line"><a id="l00073" name="l00073"></a><span class="lineno">   73</span><span class="comment"> *</span></div>
<div class="line"><a id="l00074" name="l00074"></a><span class="lineno">   74</span><span class="comment"> * @todo ipc::util::Default_init_allocator should be moved into Flow&#39;s `flow::util`.</span></div>
<div class="line"><a id="l00075" name="l00075"></a><span class="lineno">   75</span><span class="comment"> *</span></div>
<div class="line"><a id="l00076" name="l00076"></a><span class="lineno">   76</span><span class="comment"> * ### Source ###</span></div>
<div class="line"><a id="l00077" name="l00077"></a><span class="lineno">   77</span><span class="comment"> * I (ygoldfel) took it from the above link(s), made stylistic edits, and added documentation.  This is legal.</span></div>
<div class="line"><a id="l00078" name="l00078"></a><span class="lineno">   78</span><span class="comment"> *</span></div>
<div class="line"><a id="l00079" name="l00079"></a><span class="lineno">   79</span><span class="comment"> * @tparam T</span></div>
<div class="line"><a id="l00080" name="l00080"></a><span class="lineno">   80</span><span class="comment"> *         The type managed by this instance of the allocator.</span></div>
<div class="line"><a id="l00081" name="l00081"></a><span class="lineno">   81</span><span class="comment"> *         See `Allocator` concept (in standard or cppreference.com).</span></div>
<div class="line"><a id="l00082" name="l00082"></a><span class="lineno">   82</span><span class="comment"> * @tparam Allocator</span></div>
<div class="line"><a id="l00083" name="l00083"></a><span class="lineno">   83</span><span class="comment"> *         The `Allocator` being adapted.  Usually one uses the heap-allocating `std::allocator` which is the default</span></div>
<div class="line"><a id="l00084" name="l00084"></a><span class="lineno">   84</span><span class="comment"> *         arg for STL-compliant containers usually.  However it may well be something more advanced</span></div>
<div class="line"><a id="l00085" name="l00085"></a><span class="lineno">   85</span><span class="comment"> *         such as SHM-allocating ipc::shm::stl::Stateless_allocator or alias ipc::shm::classic::Pool_arena_allocator.</span></div>
<div class="line"><a id="l00086" name="l00086"></a><span class="lineno">   86</span><span class="comment"> */</span></div>
<div class="line"><a id="l00087" name="l00087"></a><span class="lineno">   87</span><span class="keyword">template</span> &lt;<span class="keyword">typename</span> T, <span class="keyword">typename</span> Allocator&gt;</div>
<div class="line"><a id="l00088" name="l00088"></a><span class="lineno"><a class="line" href="classipc_1_1util_1_1Default__init__allocator.html">   88</a></span><span class="keyword">class </span><a class="code hl_class" href="classipc_1_1util_1_1Default__init__allocator.html">Default_init_allocator</a> : <span class="keyword">public</span> <a class="code hl_class" href="classAllocator.html">Allocator</a></div>
<div class="line"><a id="l00089" name="l00089"></a><span class="lineno">   89</span>{</div>
<div class="line"><a id="l00090" name="l00090"></a><span class="lineno">   90</span><span class="keyword">public</span>:</div>
<div class="line"><a id="l00091" name="l00091"></a><span class="lineno">   91</span>  <span class="comment">// Constructors/destructor.</span></div>
<div class="line"><a id="l00092" name="l00092"></a><span class="lineno">   92</span><span class="comment"></span> </div>
<div class="line"><a id="l00093" name="l00093"></a><span class="lineno">   93</span><span class="comment">  /// Inherit adaptee allocator&#39;s constructors.</span></div>
<div class="line"><a id="l00094" name="l00094"></a><span class="lineno">   94</span><span class="comment"></span>  <span class="keyword">using </span>Allocator::Allocator;</div>
<div class="line"><a id="l00095" name="l00095"></a><span class="lineno">   95</span> </div>
<div class="line"><a id="l00096" name="l00096"></a><span class="lineno">   96</span>  <span class="comment">// Methods.</span></div>
<div class="line"><a id="l00097" name="l00097"></a><span class="lineno">   97</span><span class="comment"></span> </div>
<div class="line"><a id="l00098" name="l00098"></a><span class="lineno">   98</span><span class="comment">  /**</span></div>
<div class="line"><a id="l00099" name="l00099"></a><span class="lineno">   99</span><span class="comment">   * Satisfies `Allocator` concept optional requirement for in-place construction: specialized for 0-args,</span></div>
<div class="line"><a id="l00100" name="l00100"></a><span class="lineno">  100</span><span class="comment">   * i.e., value-initialization; replaces value-initialization with default-initialization.</span></div>
<div class="line"><a id="l00101" name="l00101"></a><span class="lineno">  101</span><span class="comment">   * This specialization is the reason Default_init_allocator exists at all.</span></div>
<div class="line"><a id="l00102" name="l00102"></a><span class="lineno">  102</span><span class="comment">   *</span></div>
<div class="line"><a id="l00103" name="l00103"></a><span class="lineno">  103</span><span class="comment">   * @tparam U</span></div>
<div class="line"><a id="l00104" name="l00104"></a><span class="lineno">  104</span><span class="comment">   *         Type being constructed.  See `Allocator` concept docs.</span></div>
<div class="line"><a id="l00105" name="l00105"></a><span class="lineno">  105</span><span class="comment">   * @param ptr</span></div>
<div class="line"><a id="l00106" name="l00106"></a><span class="lineno">  106</span><span class="comment">   *        Address at which to in-place-construct the `U`.</span></div>
<div class="line"><a id="l00107" name="l00107"></a><span class="lineno">  107</span><span class="comment">   */</span></div>
<div class="line"><a id="l00108" name="l00108"></a><span class="lineno">  108</span>  <span class="keyword">template</span>&lt;<span class="keyword">typename</span> U&gt;</div>
<div class="line"><a id="l00109" name="l00109"></a><span class="lineno">  109</span>  <span class="keywordtype">void</span> <a class="code hl_function" href="classipc_1_1util_1_1Default__init__allocator.html#a56c4ab4a0b12a26f177c35d50b96f27f">construct</a>(U* ptr) <span class="keyword">noexcept</span>(std::is_nothrow_default_constructible_v&lt;U&gt;);</div>
<div class="line"><a id="l00110" name="l00110"></a><span class="lineno">  110</span><span class="comment"></span> </div>
<div class="line"><a id="l00111" name="l00111"></a><span class="lineno">  111</span><span class="comment">  /**</span></div>
<div class="line"><a id="l00112" name="l00112"></a><span class="lineno">  112</span><span class="comment">   * Satisfies `Allocator` concept optional requirement for in-place construction: non-specialized version</span></div>
<div class="line"><a id="l00113" name="l00113"></a><span class="lineno">  113</span><span class="comment">   * invoked for 1+ args.  This behaves identically to the adaptee allocator.</span></div>
<div class="line"><a id="l00114" name="l00114"></a><span class="lineno">  114</span><span class="comment">   *</span></div>
<div class="line"><a id="l00115" name="l00115"></a><span class="lineno">  115</span><span class="comment">   * @tparam U</span></div>
<div class="line"><a id="l00116" name="l00116"></a><span class="lineno">  116</span><span class="comment">   *         Type being constructed.  See `Allocator` concept docs.</span></div>
<div class="line"><a id="l00117" name="l00117"></a><span class="lineno">  117</span><span class="comment">   * @tparam Args</span></div>
<div class="line"><a id="l00118" name="l00118"></a><span class="lineno">  118</span><span class="comment">   *         Constructor args (1+ of them).</span></div>
<div class="line"><a id="l00119" name="l00119"></a><span class="lineno">  119</span><span class="comment">   * @param ptr</span></div>
<div class="line"><a id="l00120" name="l00120"></a><span class="lineno">  120</span><span class="comment">   *        Address at which to in-place-construct the `U`.</span></div>
<div class="line"><a id="l00121" name="l00121"></a><span class="lineno">  121</span><span class="comment">   * @param args</span></div>
<div class="line"><a id="l00122" name="l00122"></a><span class="lineno">  122</span><span class="comment">   *        See `Args...`.</span></div>
<div class="line"><a id="l00123" name="l00123"></a><span class="lineno">  123</span><span class="comment">   */</span></div>
<div class="line"><a id="l00124" name="l00124"></a><span class="lineno">  124</span>  <span class="keyword">template</span>&lt;<span class="keyword">typename</span> U, <span class="keyword">typename</span>... Args&gt;</div>
<div class="line"><a id="l00125" name="l00125"></a><span class="lineno">  125</span>  <span class="keywordtype">void</span> <a class="code hl_function" href="classipc_1_1util_1_1Default__init__allocator.html#a56c4ab4a0b12a26f177c35d50b96f27f">construct</a>(U* ptr, Args&amp;&amp;... args);</div>
<div class="line"><a id="l00126" name="l00126"></a><span class="lineno">  126</span>}; <span class="comment">// class Default_init_allocator</span></div>
<div class="line"><a id="l00127" name="l00127"></a><span class="lineno">  127</span> </div>
<div class="line"><a id="l00128" name="l00128"></a><span class="lineno">  128</span><span class="comment">// Template implementations.</span></div>
<div class="line"><a id="l00129" name="l00129"></a><span class="lineno">  129</span> </div>
<div class="line"><a id="l00130" name="l00130"></a><span class="lineno">  130</span><span class="keyword">template</span>&lt;<span class="keyword">typename</span> T, <span class="keyword">typename</span> Allocator&gt;</div>
<div class="line"><a id="l00131" name="l00131"></a><span class="lineno">  131</span><span class="keyword">template</span> &lt;<span class="keyword">typename</span> U&gt;</div>
<div class="line"><a id="l00132" name="l00132"></a><span class="lineno"><a class="line" href="classipc_1_1util_1_1Default__init__allocator.html#a56c4ab4a0b12a26f177c35d50b96f27f">  132</a></span><span class="keywordtype">void</span> <a class="code hl_function" href="classipc_1_1util_1_1Default__init__allocator.html#a56c4ab4a0b12a26f177c35d50b96f27f">Default_init_allocator&lt;T, Allocator&gt;::construct</a>(U* ptr) <span class="keyword">noexcept</span>(std::is_nothrow_default_constructible_v&lt;U&gt;)</div>
<div class="line"><a id="l00133" name="l00133"></a><span class="lineno">  133</span>{</div>
<div class="line"><a id="l00134" name="l00134"></a><span class="lineno">  134</span>  <span class="comment">// If U&#39;s default-init = value-init, this changes no behavior.  Otherwise this performs default-init (~no-op).</span></div>
<div class="line"><a id="l00135" name="l00135"></a><span class="lineno">  135</span>  ::new(<span class="keyword">static_cast&lt;</span><span class="keywordtype">void</span>*<span class="keyword">&gt;</span>(ptr)) U;</div>
<div class="line"><a id="l00136" name="l00136"></a><span class="lineno">  136</span>}</div>
<div class="line"><a id="l00137" name="l00137"></a><span class="lineno">  137</span> </div>
<div class="line"><a id="l00138" name="l00138"></a><span class="lineno">  138</span><span class="keyword">template</span>&lt;<span class="keyword">typename</span> T, <span class="keyword">typename</span> Allocator&gt;</div>
<div class="line"><a id="l00139" name="l00139"></a><span class="lineno">  139</span><span class="keyword">template</span> &lt;<span class="keyword">typename</span> U, <span class="keyword">typename</span>... Args&gt;</div>
<div class="line"><a id="l00140" name="l00140"></a><span class="lineno"><a class="line" href="classipc_1_1util_1_1Default__init__allocator.html#ac030ddf85696b12dc0429b25bf5c6100">  140</a></span><span class="keywordtype">void</span> <a class="code hl_function" href="classipc_1_1util_1_1Default__init__allocator.html#a56c4ab4a0b12a26f177c35d50b96f27f">Default_init_allocator&lt;T, Allocator&gt;::construct</a>(U* ptr, Args&amp;&amp;... args)</div>
<div class="line"><a id="l00141" name="l00141"></a><span class="lineno">  141</span>{</div>
<div class="line"><a id="l00142" name="l00142"></a><span class="lineno">  142</span>  <span class="comment">// Just do the normal thing.</span></div>
<div class="line"><a id="l00143" name="l00143"></a><span class="lineno">  143</span>  std::allocator_traits&lt;Allocator&gt;::construct(<span class="keyword">static_cast&lt;</span><a class="code hl_class" href="classAllocator.html">Allocator</a>&amp;<span class="keyword">&gt;</span>(*<span class="keyword">this</span>),</div>
<div class="line"><a id="l00144" name="l00144"></a><span class="lineno">  144</span>                                              ptr, std::forward&lt;Args&gt;(args)...);</div>
<div class="line"><a id="l00145" name="l00145"></a><span class="lineno">  145</span>}</div>
<div class="line"><a id="l00146" name="l00146"></a><span class="lineno">  146</span> </div>
<div class="line"><a id="l00147" name="l00147"></a><span class="lineno">  147</span>}; <span class="comment">// namespace ipc::util</span></div>
<div class="ttc" id="aclassAllocator_html"><div class="ttname"><a href="classAllocator.html">Allocator</a></div></div>
<div class="ttc" id="aclassipc_1_1util_1_1Default__init__allocator_html"><div class="ttname"><a href="classipc_1_1util_1_1Default__init__allocator.html">ipc::util::Default_init_allocator</a></div><div class="ttdoc">Allocator adaptor (useful for, e.g., vector that skips zero-filling) that turns a value-initializatio...</div><div class="ttdef"><b>Definition:</b> <a href="default__init__allocator_8hpp_source.html#l00088">default_init_allocator.hpp:89</a></div></div>
<div class="ttc" id="aclassipc_1_1util_1_1Default__init__allocator_html_a56c4ab4a0b12a26f177c35d50b96f27f"><div class="ttname"><a href="classipc_1_1util_1_1Default__init__allocator.html#a56c4ab4a0b12a26f177c35d50b96f27f">ipc::util::Default_init_allocator::construct</a></div><div class="ttdeci">void construct(U *ptr) noexcept(std::is_nothrow_default_constructible_v&lt; U &gt;)</div><div class="ttdoc">Satisfies Allocator concept optional requirement for in-place construction: specialized for 0-args,...</div><div class="ttdef"><b>Definition:</b> <a href="default__init__allocator_8hpp_source.html#l00132">default_init_allocator.hpp:132</a></div></div>
<div class="ttc" id="anamespaceipc_1_1util_html"><div class="ttname"><a href="namespaceipc_1_1util.html">ipc::util</a></div><div class="ttdoc">Flow-IPC module containing miscellaneous general-use facilities that ubiquitously used by ~all Flow-I...</div><div class="ttdef"><b>Definition:</b> <a href="default__init__allocator_8hpp_source.html#l00023">default_init_allocator.hpp:24</a></div></div>
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